IEEE Journal on Emerging and Selected Topics in Circuits and Systems

This paper reviews emerging nonvolatile random access memories (RAM) in recent years. It first benchmarks ferroelectric RAM (FeRAM), phase change RAM (PCRAM), resistive RAM (ReRAM), and spin-torque-transfer magnetic RAM (STT-MRAM), discussing each RAM's features and its applications. Then current status of spintronics developments including not only STT-MRAM but also nonvolatile logic LSI is descr... View full abstract»

Spin transfer torque based magnetic memories (STT-MRAMs) are leading contender for the replacement of SRAM caches. However, STT-MRAMs suffer from high write current, read/write stability conflicts and other failure mechanisms. In this paper, we present a comprehensive scaling analysis for STT-MRAMs based on in-plane and perpendicular anisotropy magnets in context to different failure mechanisms. W... View full abstract»

Spin-transfer torque random access memory (STT-RAM), as a promising nonvolatile memory technology, faces challenges of high write energy and low density. The recently developed magnetoelectric random access memory (MeRAM) enables the possibility of overcoming these challenges by the use of voltage-controlled magnetic anisotropy (VCMA) effect and achieves high density, fast speed, and low energy si... View full abstract»

We survey progress in the PCM field over the past five years, ranging from large-scale PCM demonstrations to materials improvements for high-temperature retention and faster switching. Both materials and new cell designs that support lower-power switching are discussed, as well as higher reliability for long cycling endurance. Two paths towards higher density are discussed: through 3D integration ... View full abstract»

We report an interface engineering approach to achieve a self-compliance controlled and forming-free switching in ReRAM devices based on MgO switching layers. The proposed devices showed scalability in self-compliance current with low set and reset voltages as the interfacial layer thickness was increased. The devices showed write endurance up to 1000 cycles under self-compliance controlled switch... View full abstract»

In this paper, we thoroughly investigate the characteristics of the TiN/Ti/HfO2/TiN resistive random access memory (RRAM) device. The physical mechanisms involved in the device operations are comprehensively explored from the atomistic standpoint. Self-consistent physics simulations based on a multi-scale approach are employed to achieve a complete understanding of the device physics. T... View full abstract»

Ultra-low-power embedded memory is emerging as a key challenge to design systems with stringent energy but relaxed performance constraints like various wireless sensors and Internet-of-Things (IoT) devices. This paper explores the potential of Si/Ge tunnel FETs (TFET) in designing ultra-low power embedded memory bit cells, namely, Static Random Access Memory (SRAM) and embedded Dynamic RAM (eDRAM)... View full abstract»

In this paper, we review some of the novel emerging memory technologies and how they can enable energy-efficient implementation of large neuromorphic computing systems. We will highlight some of the key aspects of biological computation that are being mimicked in these novel nanoscale devices, and discuss various strategies employed to implement them efficiently. Though large scale learning system... View full abstract»

Recently biomolecular computing platforms have been widely investigated with great potentials in both biomedical research and practices, such as using molecular structures of DNA to present the data bits and to operate the logic. Emerging CMOS/molecular hybrid (CMOL) circuitry demonstrates many overwhelming advantages compared with pure biomolecular circuitry, including the design flexibility and ... View full abstract»

Using associative memories to enable computing-with-memory is a promising approach to improve energy efficiency. Associative memories can be tightly coupled with processing elements to restore and later recall function responses for a subset of input values. This approach avoids the actual function execution on the processing element to save on energy. The challenge, however, is to reduce the ener... View full abstract»

As the fourth basic circuit element, memristor has a unique synapse-alike feature which demonstrates great potentials in neuromorphic circuit design. However, a large gap exists between the theoretical memristor characteristics and the actual device behavior. For example, though the continuous changing in resistance state is expected in neuromorphic circuit design, it is difficult to maintain arbi... View full abstract»

This paper proposes embedding 256 Kb resistive random-access memory (ReRAM) in a microcontroller unit as a data buffer for communicating with a stand-alone flash memory. In this study, the chip was manufactured using a combination of the TSMC 0.18 μm process and the Industrial Technology Research Institute ReRAM back-end-of-line process. The ReRAM was equipped with a novel sense amplifier that had... View full abstract»